Cooperative control for allowing a plurality of functions to cooperate with each other so as to increase efficiency as a whole has been adopted in various fields. For example, there is known, as an eyeball control system, Patent Document 1 invented by the same inventor as the present invention. The eyeball system is a system that controls two cameras so as to achieve conjugate and convergent movements simulating the principle of eye movement. Crossing circuits connect from one to the other and connect from the other to one, of left and right control systems for respective left and right cameras to be controlled. Using a coefficient ρr allows cooperative control of different movements (conjugate and convergent movements) in the same system to be performed for the left and right control systems.